When China banned the import of used plastics in late 2017, the move threw recycling programs worldwide into turmoil. China was the world’s top importer of plastic waste. Cities worldwide had fallen into the habit of simply shipping to China the plastic they collected from residents instead of reckoning with the waste themselves.
But many environmentalists saw a positive side to China’s import ban. Shipping plastics out of sight and out of mind was unsustainable, they claimed. China’s plastics recycling industry was haphazard and probably did more damage than good to the planet. The environmentalists predicted that the Chinese ban, though hard to swallow at the time, would lead to more investment in recycling plants worldwide.
This optimistic take seems to be playing out, and Japan is leading the charge. Japan has long been a leader in recycling technologies, but Japanese companies found it nearly impossible to deploy their processes in ways that made commercial sense. Shipping waste to China was much cheaper. Now, China’s ban and a Japanese recycling law passed in June are combining to spur expansion of Japanese plastics recycling capacity—particularly the chemical recycling techniques advocated by the chemical industry.
According to Japan’s Plastic Waste Management Institute, the country has long boasted a plastics recycling rate of 85%. But that number is misleading because it represents merely the share of plastic waste that is collected and sorted in Japan. Until 2017, a lot of it was shipped to China. And since China’s ban, a lot of it has been burned.
“Immediately after the ban, waste plastics accumulated in Japan and had nowhere to go,” says Toshiaki Yoshioka, a professor at Tohoku University’s Graduate School of Environmental Studies who specializes in the chemical recycling of plastics. Japan, he says, has no choice but to invest in local processing capacity for used plastics, a move that “has strengthened the trend that the waste must be properly recycled within Japan.”
The Act on Promotion of Resource Circulation for Plastics, a law enacted in June, is also poised to reshape Japanese plastics recycling—and Japan’s plastics industry overall.
The law encourages manufacturers to design products for ease of recycling. In addition, it requires major retailers and hotel chains to offer plastic products that are 60% derived from recycled or biodegradable materials by 2030. Also, by April, convenience stores and hotels will have to start charging for plastic items, including disposable cutlery and hotel toothbrushes. In response, retailers and hotels are mapping out plans to recycle plastic packaging or replace it with biodegradable materials such as paper.
Producers of packaging material are already feeling the changes. The beverage company Kirin Holdings, famous for its namesake beer, is a major producer of plastic containers, both for its own products and for sale to other firms. Kirin has set a target to use at least 50% recycled plastics in its products by 2027, and it is planning to build new manufacturing facilities to achieve that goal.
Through a venture with Mitsubishi Chemical announced in December, Kirin will research and develop a commercially viable process for the large-scale depolymerization of polyester bottles into monomers that can be turned into polymers again. Kirin would use the resulting product to help meet its recycling target.
The project is one of many recycling initiatives for Mitsubishi, which sees a business opportunity in the field. Today, the plastics that are recycled in Japan are typically processed by mechanical methods. But these methods have drawbacks. For example, they deteriorate the plastics’ physical properties and aren’t well suited for materials destined for food contact. Mitsubishi and other chemical makers argue that chemical recycling methods, like depolymerization, are necessary to increase recycling rates in Japan.
Another area of investment for Mitsubishi is polymethyl methacrylate (PMMA), an acrylic plastic sold under names such as Plexiglas and Lucite. Mitsubishi owns Lucite International, a maker of PMMA, and is the world’s top producer of PMMA’s monomer, methyl methacrylate. Global demand for PMMA amounts to 3.7 million metric tons (t) annually, according to Mitsubishi.
In May, Mitsubishi teamed with Osaka, Japan–based Microwave Chemical to develop a new microwave-based technology for PMMA depolymerization. The partners plan to set up a commercial plant that will start operating in 2024, producing methyl methacrylate of the same quality as virgin monomer, which Mitsubishi will use to make new PMMA.
The two firms started to test the process in July by depolymerizing waste resin at Microwave Chemical’s Osaka factory. “We’ll first start on a small scale,” says Kenichiro Mawatari, general manager of Mitsubishi’s circular economy promotion division. The two companies plan to collaborate with Honda Motor in the future to recover waste acrylic from the taillight covers of cars headed to the scrapyard. “We set our sights on recovering waste extensively in the future,” Mawatari says.
Microwave Chemical isn’t Mitsubishi’s only partner for PMMA recycling. A year ago, Mitsubishi announced that it was working with US-based Agilyx to develop new chemical recycling processes for acrylics. Initial tests of Agilyx’s method at its Oregon pyrolysis facility exceeded expectations, Mitsubishi said last year. The two partners aim to have a commercial process ready by 2023. “We are planning to build and operate PMMA recycling plants in Japan and Europe around 2024,” Mawatari says.
Recycling a clean, sorted plastic like PMMA is one thing; finding value in mixed plastic waste is more difficult. To address that challenge, Mitsubishi concluded a license agreement in June with the UK firm Mura Technology. Mitsubishi is the first international licensee for Mura’s HydroPRS process, which uses supercritical water at high temperature and pressure to turn waste plastics into an oil that can be used as fuel or as a feedstock for new chemicals.
Mitsubishi will implement Mura’s process at a plant to be built with the Japanese oil producer Eneos at Mitsubishi’s site in Ibaraki, Japan. The facility is scheduled to open in 2023 with 20,000 t per year of capacity. Almost at the same time, Idemitsu Kosan, another oil producer, will start up a 15,000 t per year plant in Chiba, Japan, that will implement a catalytic plastics recycling process from the Japanese firm Environment Energy.
Although Mitsubishi and Idemitsu are turning to new processes for their plastics recycling facilities, technology has not been the main hurdle in Japan when trying to turn waste into raw material. Rather, the primary challenge has been the availability of waste material at a commercially viable cost. Two decades ago, Japanese firms built several plants to convert waste plastics into oil, but they have since closed because the feedstock was too expensive.
Japan’s new environmental law and the loss of China as a cheap way to dispose of waste plastics are making the feedstock issue less challenging. Before the 2017 ban, Japan exported 800,000 t of waste plastics to China annually, according to Japan’s Ministry of Finance. The US shipped a similar amount, while Europe shipped about 2 million t, according to the polystyrene producer PS Japan.
“It is important to establish a cost-effective collecting system for waste plastics,” Tohoku University’s Yoshioka says. Luckily, Japan is a world leader in training its citizens to sort and dispose of their trash. In Tokyo, for example, combustible waste is gathered only on Mondays and Thursdays. Paper, glass containers, and aluminum cans are picked up every other Tuesday. Trash collectors pick up polyethylene terephthalate (PET) bottles only on certain days. Meanwhile, supermarkets have been given the job of collecting from customers the plastic trays used to package fresh food like meat and fish.
Successful collection paves the way to successful recycling, Yoshioka says. “If each local administration works out a program for collecting a sizable amount of plastic resources with certain quality, it will raise chemical recycling rates by leaps and bounds,” he says.
Japan’s Plastic Packaging Recycling Council, which represents manufacturers of confectionery, beverages, and cosmetics, says Japan can do more. “Japan lags behind Europe in sorting of plastic waste,” says Naoki Kubo, the council’s senior managing director. He adds that he saw some very advanced plastic-sorting facilities on a tour of Europe. “If the administration and privately owned corporations jointly establish a system to mechanically sort synthetic resins by their types, it will accelerate social implementation of recycling.”
One reason for the viability of Mitsubishi’s recycling venture with Eneos is the participation of Refinverse, a recycling business that Mitsubishi invested in last year. Refinverse will be responsible for supplying feedstock to the Ibaraki facility.
Executives at Teijin, a Japanese plastics and chemical producer, understand well both the convenience that Japan enjoyed in having China as an outlet and the promise of a recycling rebirth in Japan. Ten years ago, the company built a plant in China with a local partner to depolymerize used polyester clothes sent from Japan and turn them into virgin polyester. But the venture folded after China instituted its ban on importing other countries’ waste.
Teijin now wants to replicate the recycling concept at its home base. Working with the Japanese partners Itochu and JGC Holdings, the firm seeks to license the depolymerization technology in Japan and elsewhere to process either used PET bottles or discarded polyester clothing. “Chemical recycling is positioned to curtail CO2 emissions in the whole supply chain,” says Akimoto Uchikawa, an executive officer and board member at Teijin.
An advantage of the Teijin project is its reliance on proven technology. Several firms have sought to license it, Uchikawa says.
When it comes to the public’s awareness of plastic waste, polystyrene probably tops the list. In years past, public pressure forced fast-food makers around the world to abandon polystyrene foam clamshells and use paper or aluminum wrappers instead. Seeking to fend off more loss of business, several Japanese companies are expanding their efforts to develop commercial methods of recycling polystyrene waste.
PS Japan, for instance, is building a 1,000 t per year demonstration plant in Mizushima, Japan, that will turn polystyrene food trays and containers back into styrene. The plant, cobuilt with Toshiba Plant Systems & Services, is scheduled to open in December 2022. PS Japan, Japan’s largest polystyrene producer, is owned by Asahi Kasei and Idemitsu Kosan. If the Mizushima plant works as expected, PS Japan plans to start up a larger facility in 2025.
Toshiba Plant Systems & Services has been working on polystyrene recycling for many years. With a subsidy from the New Energy and Industrial Technology Development Organization, Toshiba built its first polystyrene recycling plant in 2001. The small facility produced styrene that was 99.7% pure, meeting quality standards set by Japan Industrial Standards and ASTM International. It also successfully processed 60% of the polystyrene waste fed into it.
But the plant closed in 2005 because, at the time, it made more economic sense to ship polystyrene waste to China. “In those days, exports of used plastics to China had higher economic efficiency than recycling them in Japan,” says Kenji Omi, general manager of PS Japan’s sustainability planning division. “We couldn’t collect a sufficient amount of used styrene products,” Omi says.
Now, the company is revisiting polystyrene recycling. Takenori Kondo, the firm’s managing director, says PS Japan is exploring opening a recycling facility in 2024.
China’s abrupt end to waste plastic imports is brightening prospects for firms like PS Japan that couldn’t obtain enough material until recently. Japan is not alone in feeling the effect of China’s ban on waste plastic imports. But that ban, and the extra pressure of the country’s strict new recycling law, is leading to a rapid buildup of the country’s recycling infrastructure.
“We should soon be able to raise the scale of chemical recycling to 2.5–3 million t per year,” Tohoku University’s Yoshioka says. Rather than exporting its plastic waste to China, Japan could someday be importing it from other countries.
Katsumori Matsuoka is a freelance writer based in Japan.